System and method for tracking ammunition

ABSTRACT

A system and method for tracking ammunition, including a magazine that stores ammunition rounds, a top plate that slides along a longitudinal axis of the magazine, and a processing unit that determines the number of ammunition rounds in the magazine based on the position of the top plate. The system may output the number of ammunition rounds in the magazine to a display and/or store a time stamp indicative of each time a round was chambered and/or fired.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Appl. No. 62/017,643, filed Jun. 26, 2014, and U.S. Provisional Appl. No. 62/060,371, filed Oct. 6, 2014, the entire content of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

An accurate count of the number of rounds included in a firearm magazine enables a user to better anticipate the need to replace the magazine in the firearm. Furthermore, sharing information regarding ammunition enables better coordination of military and law enforcement personnel. For example, one individual with excess ammunition may coordinate with another individual who has spent more ammunition if information regarding ammunition is shared between military or law enforcement personnel. In another example, accurate ammunition tracking allows supervisory or support personnel to resupply military or law enforcement personnel. If military or law enforcement personnel are better able to be resupplied, those military or law enforcement members are able to carry less ammunition with the confidence that the will be resupplied when necessary.

Additionally, after a firearm is discharged, an objective and accurate record of the time that each ammunition round may help corroborate or disprove a witnesses' statement of events. For example, in the aftermath of a shooting, a law enforcement official may give testimony as to the time of a shooting and the number of rounds discharged. In this instance, an objective and accurate record of the firing of each round may corroborate the evidence presented by the law enforcement official.

Conventional firearms do not provide these benefits. Accordingly, there is a need for an improved system and method for tracking ammunition.

SUMMARY OF INVENTION

According to an aspect of an exemplary embodiment, there is provided a system and method for tracking ammunition, including a magazine that stores ammunition rounds, a top plate that slides along a longitudinal axis of the magazine, and a processing unit that determines the number of ammunition rounds in the magazine based on the position of the top plate. The system may output the number of ammunition rounds in the magazine to a display and/or store a time stamp indicative of each time a round was chambered and/or fired.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of exemplary embodiments may he better understood with reference to the accompanying drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of exemplary embodiments.

FIG. 1 is an overview of a weapons system according to an exemplary embodiment of present invention;

FIGS. 2A and 2B are overviews of a magazine according to exemplary embodiments of the present invention;

FIG. 3 is a profile view of a heads up display according to an exemplary embodiment of the present invention;

FIG. 4 is an overview of a reflex sight display according to an exemplary embodiment of the present invention; and

FIG. 5 is a flowchart illustrating a process for tracking ammunition according to an exemplary embodiment of the present invention; and

FIGS. 6A, 6B, and 6C are flowcharts illustrating processes for tracking ammunition chambering and firing according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Reference will now be made in detail to exemplary embodiments by way of reference to the accompanying drawings, wherein like reference numerals refer to like parts, components, and structures.

FIG. 1 is an overview of a weapons system 100 according to an exemplary embodiment of the present invention. The weapons system 100 includes a firearm 110, one or more magazines 200, and a heads up display (HUD) 300.

FIG. 2A illustrates a magazine 200 according to an exemplary embodiment of the present invention. The magazine 200 includes a magazine spring 206, one or more rounds 208, and a top plate 214. The magazine 200 also includes a magazine processing unit 220, an on/off sensor 222, a magazine power source 230, and a magazine database 240.

As rounds 208 are added to the magazine 200, the downward pressure of each round 208 pushes the top plate 214 towards the bottom of the magazine 200 and condenses the magazine spring 206. As each round 208 is removed (either manually or by chambering the rounds 208 in the firearm 110), the energy stored in the magazine spring 206 pushes the top plate 214 up towards the top of the magazine 200.

The magazine processing unit 220 includes instructions to determine the number of rounds 208 in the magazine 200 based on the relative position of the top plate 214. For example, the magazine 200 may include a close circuit system 210 a. The close circuit system 210 a includes a power rail 212, a conductive portion of the top plate 214, and a plurality of electrodes 216 that are each be individually connected to the magazine processing unit 220. As the top plate 214 moves up and down the magazine 200, the conductive portion of the top plate 214 completes a circuit from the power rail 212 to one or the plurality of electrodes 216 and the magazine processing unit 220 determines the relative position of the top plate 214 based on which one of the plurality of electrode 216 is connected to the power rail 212 by the conductive portion of the top plate 214.

The power rail 212 receives power from the magazine power source 230. The top plate 214 may be conductive or may include a conductive portion. In either instance, the top plate 214 electrically connects the power rail 212 and one of the plurality electrodes 216 based on the relative position of the top plate 214. Because the rounds 208 are a standard dimension, the electrodes 216 may be evenly spaced in a longitudinal direction. The electrodes 216 include a first electrode 216 a located such that it is electrically connected to the conductive portion of the top plate 214 when the magazine 200 is empty, a second electrode 216 b located such that it is electrically connected to the conductive portion of the top plate 214 when the magazine 200 includes one round 208, additional electrodes at evenly spaced intervals in the longitudinal direction, and a final electrode 216 n located such that it is electrically connected to the conductive portion of the top plate 214 when the magazine 200 is full.

In the exemplary embodiment illustrated in FIG. 2A, the magazine processing unit 220 is configured to determine and store the number of rounds 208 in the magazine based on a signal from the close circuit system 210 a indicative of the identity of the electrode 216 electrically connected to the power rail 212 by the conductive portion of the top plate 214.

FIG. 2B illustrates the close circuit system 210 b according to another exemplary embodiment of the present invention. Similar to close circuit system 210 a, the close circuits system 210 includes a power rail 212 and a conductive portion of the top plate 214. Instead of the plurality of electrodes 216, however, the close circuit system 210 b includes a resistive element 218 located along the longitudinal direction of the magazine 200 and electrically connected to the magazine processing unit 220. As the top plate 214 moves up and down the magazine 200, the top plate 214 conductor completes a circuit from the power rail 212 to the resistive element 218. In the exemplary embodiment illustrated in FIG. 2B, the close circuit system 210 b forms a variable resistor with the conductive portion of the top plate 214 acting as the sliding contact along the resistive clement 218.

The resistance of the resistive element 218 is proportional to the distance from the base of the resistive element 218 to the junction of the resistive element 218 and the conductive portion of the top plate 214. Similar to the close circuit system 210 a, the close circuit system 210 b supplies power to the power rail 212 and the conductive portion of the top plate 214. As one of ordinary skill in the art would recognize, the voltage of the circuit formed by the close circuit system 210 b is equal to the current multiplied by the resistance of the circuit and, because the resistance of the power rail 212 and the conductive portion of the top plate 214 is negligible, the resistance of the circuit is substantially equal to the resistance of the resistive element 218. Accordingly, the magazine processing unit 220 may be configured to determine the relative position of the top plate 214 by applying a constant voltage between the power rail 212 and the base of the resistive element 218 measuring the current. Alternatively, the magazine processing unit 220 may supply a constant current to the power rail 212 and measure the voltage between the power rail 212 and the base of the resistive element 218.

In the exemplary embodiment illustrated in FIG. 2B, the magazine processing unit 220 is configured to determine and store the number of rounds 208 in the magazine based on a signal from the close circuit system 210 b indicative of the relative position of the top plate 214. The position of the top plate 214 relative to the top of the magazine 200 is the difference between the total height of the magazine and the distance from the base of the resistive element 218 to the junction of the resistive element 218 and the conductive portion of the top plate 214, which, as described above, is determined based on the resistance of the circuit.

The magazine processing unit 220 includes a transmitter that outputs a signal to the firearm 110 indicative of the number of rounds 208 in the magazine 200. The transmitter may be any suitable device configured to output a signal to the firearm 110, including a wired transmitter or wireless transmitter. The wireless transmitter may output a frequency modulated radio signal according to a known standard such as Bluetooth or any other radio frequency communications method.

The magazine processing unit 220 determines whether the magazine 200 is an active magazine (i.e., if the magazine 200 includes at least one round 208) based on the output of the close circuit system 210 and outputs a signal to the firearm 110 that the magazine 200 is an active magazine. When the magazine 200 is placed in the firearm 110, the on/off sensor 222 makes contact with the firearm 110. Based on the output of the on/off sensor 222, the magazine processing unit 220 determines that that the magazine 200 is in the firearm 110 and outputs a signal to the HUD 300 indicative of the number of rounds 208 in the magazine 200.

FIG. 3 illustrates a profile view of a HUD 300 according to an exemplary embodiment of the present invention. The HUD 300 is mounted to a picatinny rail 310 and includes a reflex sight display 320, reflex sight hardware 330, a HUD power source 340, a HUD processing unit 350, a firing sensor 360, and a HUD database 370.

FIG. 4 illustrates a view of the reflex sight display 320 of FIG. 3 according to an exemplary embodiment of the present invention. The reflex sight display 320 may be a reflective display, a partially reflecting glass element such that an illuminated projection is superimposed on the field of view. Alternatively, the display 320 may be any display (e.g., a liquid crystal display (LCD), light emitting diode (LED), organic light emitting diode (OLED)) that outputs age (for example, from a camera mounted on the firearm 110) and the illuminated projection. As illustrated in FIG. 4, the illuminated projection may include a directional indicator 410, a wireless communications indicator 420, a cross hair 430, a magazine indicator 440, a power source indicator 450 and a round indicator 460.

The directional indicator 410 indicates a direction (e.g., a cardinal direction) of the firearm 110. The wireless communications indicator 420 indicates whether the HUD 300 is in wireless communication with one or more magazines 200. The cross hair 430 is located in an optically appropriate position to give an accurate aiming point of the firearm 110. The cross hair 430 may be embedded fibers, engraved lines or a computer-generated image superimposed on a screen.

The magazine indicator 440 is indicative of the number of active magazines 300 carried by the user. For instance, the magazine indicator 440 may indicate the number of active magazines 300 within wireless range of the HUD 300. Because the magazine indicator 440 is limited by the wireless range of the HUD 300, the magazine indicator 440 will count only the magazines carried by the user. (If, for example, a soldier leaves a fully loader magazine 200 back in the base, it will not be in range and therefore will not be included in the count of magazines 200 output by the magazine indicator 440). The power source indicator 450 may be an indication proportional to the estimated lifespan of the HUD power source 340 and/or the magazine power source 230. The round indicator 460 may indicate the number of rounds in the magazine 200 currently in the firearm 110.

Each time the firearm 110 discharges a round 208, the round indicator 460 is reduced by one. When all of the rounds 208 of a a magazine 200 are discharged, the magazine processing unit 220 no longer outputs a signal indicating that the magazine 200 is active and the magazine indicator 440 is reduced by one.

FIG. 5 is a flowchart illustrating a process 500 for tracking ammunition according to an exemplary embodiment of the present invention. The system 100 is turned on in step 502. The HUD 300 determines the number of active magazines 200 within wireless range in step 504. The HUD displays a magazine indicator 440 based on the number of active magazines 300 within wireless range of the HUD 300 in step 506. The magazine processing unit 220 determines number of rounds 208 in the magazine 200 based on the relative position of the top plate 214 in step 508 and transmits the number of rounds 208 to the HUD 300 in step 510. The HUD 300 displays a round indicator 460 based on the number of rounds 208 in the magazine 200 in step 512. The steps 504 through 514 are repeatedly performed so that the magazine indicator 400 and the round indicator 460 may be updated to reflect changes in the number of active magazines 200 and/or rounds 208. In order to conserve power, the magazine 200 and HUD 300 enter sleep mode in step 518 (for example, in the HUD 301) and/or magazine 200 are inactive for a pre-determined period of time) The HUD 300 and/or the magazine 200 determine whether the conditions to enter sleep mode have been satisfied in step 514.

The process 500 may be stored as instructions in any non-transitory computer readable storage medium and executed by one or more processors for example, the magazine processing unit 220 and/or the HUD processing unit 350).

The HUD 300 may also wirelessly transmit information indicative of the number of rounds 208 in an active magazine 200 and the number of the active magazines 200 carried by a user to team commanders, unit commanders etc. This wireless communication will provide real-time or near real-time communication to appropriate personnel when a soldier is discharging his or her weapon. Ammunition consumption information as well as the location of the firearm 110 may be displayed, for example, on a topographical map. The location of the firearm 110 may he determined by global positioning satellites (GPS) and output by the HUD 300. Accordingly, based on the consumption speed of munitions, appropriate personal may determine whether a soldier is coming under heavy fire and determine if additional personnel and/or additional ammunition should be deployed.

The wireless signals output by the magazine 200 and/or the HUD 300 may be encrypted. If the HUD power source 340 and/or the magazine power source 230 is such that it will soon no longer able to supply power, the HUD 300 may output a “last call” wireless signal to alert appropriate personnel that the unit is terminating. The “last call” wireless signal may include, for example, the time, date and location of the termination.

The wireless signals output by the magazine 200 and/or the HUD 300 may also be used by law enforcement. For example, if a suspect is in possession of a firearm 110, the wireless signals output by the magazine 200 and/or the HUD 300 may indicate to law enforcement personnel that the suspect is armed, whether a magazine 200 is active, weather a round 208 is chambered, etc.

Areas where firearms are prohibited such as schools and federal buildings may include fencing that uses the wireless signals output by the magazine 200 and/or the HUD 300 to detect the presence of the firearm 110, whether a magazine 200 is active, weather a round 208 is chambered, etc.

The weapons system 100 may also be configured to store a time stamp indicative of a time each round 208 is chambered and/or tired. Referring back to FIG. 3, the HUD 300 may include a firing sensor 360 and a HUD database 370. The firing sensor 360 may detect if and when the rearm 110 fires a round 208 and output a signal based on a determination that the firearm 110 has fired round 208. In response to the signal from the firing sensor 360, the HUD processing unit 350 may be further configured to store a time stamp indicative of the time each round 208 is fired in the HUD database 370. The time stamp stored by the HUD processing unit 350 may be indicative of the time of day or may be relative to the time that the previous round 208 was fired. The firing sensor 360 may be any suitable device capable of detecting if and when the firearm 110 fires a round 208. For example, the firing sensor 360 may be a motion sensor configured to output a signal based on a motion of the firearm 208 indicative of the recoil from firing a round 208. The faring sensor 360 may be located in the HUD 300 as shown in FIG. 3. Alternatively the firing sensor 360 may be separately located from the HUD 300 (for example, incorporated within the firearm 110).

Referring back to FIG. 2, the magazine 200 may include a magazine database 240. The magazine processing unit 220 may be configured to store a time stamp indicative of the time each round 208 is chambered in the magazine database 240. The magazine processing unit 220 may determine the time each round is chambered based on the relative position of the top plate 214 as described above. In other words, in response to a determination that the top plate 214 has moved upwards by a distance indicative of the chambering of a round 208, the magazine processing unit may determine the no and store a time stamp in the magazine database 240. The time stamp stored by the magazine processing unit 220 may be indicative of the time of day or may be relative to the time that the previous round 208 was chambered.

The HUD 300 and the magazine 200 may be configured to store two redundant time stamps for each round 208. Because the firing of a round and the chambering of the subsequent round are nearly contemporaneous, the HUD processing unit 350 may determine the time a round 208 was fired based on the output of the firing sensor 360 as described above and the magazine processing unit 220 may determine the time that the round 208 was fired based on the chambering of the subsequent round 208.

In order to save power, the system 100 may be configured such that the magazine 200 enters a low power mode and the 300 outputs a signal to the magazine 200 in response to a determination that a round 208 has been fired. In this instance, instead of storing a time stamp indicative or the chambering of the subsequent round 208, the magazine processing unit 220 may be configured to determine and store a time stamp based on the time the signal was received from the HUD 300.

The magazine processing unit 220 may transmit the time stamp(s) determined by the magazine processing unit 220 to the HUD 300. The HUD 300 may store the time stamp(s) received from the indicative of the chambering of each round 208 in the HUD database 370 along with the time stamps indicative of the firing of each round 208. The redundancy of the double time stamp allows precision timing and compensates for any data loss in the event that communication between the magazine 200 and the HUD 300 is interrupted. Transmissions to and from the magazine 200 and the HUD 300 may be wired or wireless as described above. The HUD 300 may transmit the time stamps indicative of the chambering and/or firing of each round 208 to appropriate personnel as described above. Wireless transmissions may be encrypted as described above.

FIG. 6A is a flowchart illustrating a method of tracking ammunition fining according to an exemplary embodiment of the present invention. The HUD 300 is turned on in step 620. In step 622, the HUD processing unit 350 determines whether a round 208 is fired based on the output of the firing sensor 360. If the HUD processing unit 350 determines that a round 208 is fired (Step 622: Yes), the HUD processing unit 350 determines the time indicative of the firing of the round 208 in step 624 and stores a time stamp indicative of the firing of the round 208 in the HUD database 370 in step 626. The HUD 300 may transmit the time stamp or time stamps to appropriate personnel in step 628. In order to conserve power, the HUD 300 may enter sleep mode in step 616.

FIG. 6B is a flowchart illustrating a process 600 b of tracking ammunition chambering according to an exemplary embodiment of the present invention. The magazine 200 is turned on in step 640. In step 642, the magazine processing unit 220 determines whether a round 208 is chambered. If magazine processing unit 220 determines whether a round 208 is chambered (Step 642: Yes), the magazine processing unit 220 determines a time indicative of the chambering of the round 208 in step 644 and stores a time stamp indicative of the chambering of the round 208 in the magazine database 240 in step 646. The magazine 300 may transmit the time stamp to the HUD 300 in step 648. In order to conserve power, the magazine 200 may enter sleep mode in step 650.

FIG. 6B is a flowchart illustrating a process 600 e for tracking ammunition firing according to another exemplary embodiment of the present invention. Similar to the process 600 a, the process 600 c includes steps 620 through 626 wherein the HUD 300 determines and stores a time stamp indicative of the firing of a round 208. The HUD 300 may output a signal to the magazine 200 requesting an additional timestamp in step 630 and, in response, the magazine processing unit 220 may determine, store and transmit to the HUD 300 a time stamp indicative of the time of receipt of the signal from the HUD 300 in steps 632, 646, and 648. (Instead of determining, storing, and transmitting the time stamp in response to a signal from the HUD 300, the magazine processing unit 200 may determine the time stamp based on the chambering of the next round 208. In other words, steps 630 and 632 of the process 600 c may be replaced with steps 642 and 644 of the process 600 b.) The HUD processing unit 350 stores the time stamp received from the magazine 200 in the HUD database 370 in step 660. The HUD 300 may transmit the time stamp determined by the HUD 300 and/or the time stamp received from the magazine 200 to appropriate personnel in step 622. In order to conserve power, the magazine 200 and the HUD 300 may enter sleep mode in step 680.

The processes 600 a-c may be stored as instructions in any non-transitory computer readable storage medium and executed by one or more processors (for example, the magazine processing unit 220 and/or the HUD processing unit 350).

The foregoing description and drawings should be considered as illustrative only of the principles of the inventive concept. Exemplary embodiments may be realized in a variety of shapes and sizes and are not intended to be limited by the preferred embodiments described above. Numerous applications of exemplary embodiments will readily occur to those skilled in the art. Therefore, it is not desired to limit the inventive concept to the specific examples disclosed or the exact construction and operation shown and described. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of this application. 

What is claimed is:
 1. A system, comprising: a magazine configured to store a plurality of ammunition rounds, the magazine comprising a top plate configured to slide along a longitudinal axis of the magazine; a processing unit configured determine a number of ammunition rounds in the magazine based on a relative position of the top plate.
 2. The system of claim 1, further comprising a close circuit system, wherein: the close circuit system comprises: a power rail located along the longitudinal axis of the magazine; and a plurality of electrodes located along the longitudinal axis, each of the plurality of electrodes electrically connected to the processing unit; the top plate includes a conductive portion electrically connecting the power rail to one of the plurality of electrodes based on the relative position of the top plate; and the processing unit is configured to determine the relative position of the top plate based on the electrode electrically connected to the power rail.
 3. The system of claim 1, further comprising a close circuit system, wherein: the close circuit system comprises: a power rail located along the longitudinal axis of the magazine; and a resistive element located along the longitudinal axis; the top plate includes a conductive portion electrically connecting the power rail to the resistive element to form a closed circuit; and the processing unit is configured to determine the relative position of the top plate based on an electrical resistance of the closed circuit.
 4. The system of claim 1, wherein the processing unit is further configured to output a round indicator indicative of the number of ammunition rounds in the magazine; and a display configured to output the round indicator.
 5. The system of claim 4, wherein the processing unit wirelessly transmits the round indicator the display.
 6. The system of claim 5, wherein the display is further configured to output a magazine indicator indicative of a number of magazines within wireless range that include at least one ammunition round.
 7. The system of claim 6, wherein the system is configured to wirelessly transmit the magazine indicator.
 8. The system of claim 4, wherein the display is mounted on a firearm.
 9. The system of claim 1 wherein the magazine further comprises a magazine database and the processing unit is configured to store time stamps indicative of the chambering of each of the ammunition rounds in the magazine database.
 10. The system of claim 1, wherein the display further comprises a display database and the display is further configured to store time stamps indicative of the firing of each of the ammunition rounds in the display database based on the output of a firing sensor.
 11. A method for tracking ammunition, the method comprising: determining, by a processing unit, a number of ammunition rounds in a magazine configured to store the ammunition rounds based on a relative position of a top plate configured to slide along a longitudinal axis of the magazine.
 12. The method of claim 11, further comprising: outputting power by a power rail located along the longitudinal axis; providing a plurality of electrodes located along the longitudinal axis, each of the plurality of electrodes electrically connected to the processing unit; electrically connecting, by a conductive portion of the top plate, the power rail to one of the plurality of electrodes based on the relative position of the top plate; and determining, by the processing unit, the relative position of the top plate based on the electrode electrically connected to the power rail.
 13. The method of claim 11, further comprising: outputting power by a power rail located along the longitudinal axis; providing a resistive element located along the longitudinal axis; electrically connecting, by a conductive portion of the top plate, the power rail to the resistive element to form a closed circuit; and determining, by the processing unit, the relative position of the top plate based on a resistance of the closed circuit.
 14. The method of 11, further comprising: outputting, by the processing unit, a round indicator indicative of the number of ammunition rounds in the magazine; and outputting, by the display, the round indicator.
 15. The method of claim 14, further comprising: wirelessly transmitting, by the processing unit, the round indicator to the display.
 16. The method of claim 15, further comprising: outputting, by the display, a magazine indicator indicative of a number of magazines within wireless range that at least one ammunition round.
 17. The method of claim 16, further comprising: wirelessly transmitting, by the display, the magazine indicator.
 18. The method of claim 17, further comprising: mounting the display on a firearm.
 19. The system of claim 11, further comprising: determining a time indicative of a chambering one of the plurality of ammunition rounds based on a change in the relative position of the top plate: storing a time stamp indicative of the tune in a database.
 20. The method of claim 11, further comprising: determining a time indicative of a firing of one of the plurality of ammunition rounds based on an output of a firing sensor; storing a time stamp indicative of the time in a database. 